The present invention is concerned in particular with trailer-type carriers for heavy machinery, such as machinery for public works, agricultural machines, and the like.
A pivotable connecting mechanism of this type of trailer to the prime mover is implemented in the form of a curved connecting arm of large dimensions, conventionnaly called a "swan neck".
Such an arm is of large dimensions, because of the strong forces acting on the prime mover by the weight of the transported engine. Furthermore, the arm is curved, so as to permit a sufficient lowering thereof in the case of any uneven ground, or due to a ground criss-crossed by troughs, and/or due to other unevenness of the terrain.
For the aforesaid reasons the arm connecting the trailer with the prime mover is conventionally called an unhooked "swan neck".
In order to permit access to the platform of the trailer, the trailer is conventionally equipped on its rear with lowerable access ramps for each wheel of any wheel-train of the engines transported.
For the same reasons of required mechanical strength, the ramps are made to be heavy and strong.